Oxidative coupling of alkylphenols catalyzed by metal ammonia complexes

Abstract

Carbon-carbon coupled self-condensation products obtained by the oxidative coupling of alkylphenols are prepared by contacting an aqueous mixture of an alkyl phenol with oxygen in the presence of sufficient alkaline material to sustain a pH in the range of 6-9.5 during the oxidative coupling reaction and a catalyst system comprising an ammonia complex of monovalent copper; divalent copper, cobalt, nickel or manganese; or trivalent chromium or iron. The mixture may optionally contain a surfactant.

What is claimed is: 
     
       1. A method of preparing a condensation product of an "alkylphenol", an "alkoxyphenol" or a "1-naphthol", by an oxidative coupling reaction said method comprising contacting an aqueous mixture of the phenol or naphthol with oxygen or oxygen containing gas in the presence of sufficient amount of alkaline material to sustain pH in the range of about 6-9.5 during the oxidative coupling reaction and a catalyst system comprising an ammonia complex of monovalent copper; divalent copper, cobalt, nickel or manganese; or trivalent chromium or iron. 
     
     
       2. A method, as claimed in claim 1, wherein the aqueous phenol mixture addtionally comprises a surfactant. 
     
     
       3. A method, as claimed in claim 2, wherein the surfactant is sodium lauryl sulfate and is present in an amount equal to at least 0.005 mols per mol of phenol or naphthol. 
     
     
       4. A method, as claimed in claim 1, wherein the phenol is an alkylphenol. 
     
     
       5. A method, as claimed in claim 4, wherein the alkylphenol is a 2,6-dialkylphenol. 
     
     
       6. A method, as claimed in claim 5, wherein the alkylphenol is 2,6-xylenol. 
     
     
       7. A method, as claimed in claim 4, wherein the alkyl groups of said alkylphenol contain from 1 to about 12 carbon atoms. 
     
     
       8. A method, as claimed in claim 4, wherein the alkyl groups of said alkylphenol contain from 1 to about 5 carbon atoms. 
     
     
       9. A method, as claimed in claim 1, wherein the catalyst system comprises a cupric ammonia complex. 
     
     
       10. A method, as claimed in claim 9 wherein the alkylphenol is 2,6-xylenol. 
     
     
       11. A method, as claimed in claim 1, wherein the amount of metal complex is equal to at least about 0.2 mmols per mol of phenol or naphthol. 
     
     
       12. A method, as claimed in claim 1, wherein the alkaline material is an alkali metal bicarbonate. 
     
     
       13. A method, as claimed in claim 12, wherein the alkali metal bicarbonate is sodium bicarbonate. 
     
     
       14. A method, as claimed in claim 1, wherein the amount of alkaline material is equal to at least about 3 mmols per mol of phenol or naphthol. 
     
     
       15. A method, as claimed in claim 1, wherein the phenol is an alkylphenol having the following formula: ##STR14## wherein R 2  and R 6  are alkyl and R 3  and R 5  are hydrogen or alkyl and R 4  is hydrogen or methyl provided that R 3  and R 5  cannot be both tertiary alkyl. 
     
     
       16. A method, as claimed in claim 15, wherein the alkyl phenol is 2,4,6-trimethylphenol.